不溶性骨架材料（）. A．Ⅱ号、Ⅲ号丙烯酸树脂 B．羟丙甲纤_爱下问搜题

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问题单项选择题

不溶性骨架材料（）.

A．Ⅱ号、Ⅲ号丙烯酸树脂

B．羟丙甲纤维素

C．硅橡胶

D．离子交换树脂

E．鞣酸

答案

参考答案：C

解析：

本题考查常用包衣材料和骨架材料。 Ⅱ号、Ⅲ号丙烯酸树脂属于肠溶包衣。羟丙甲纤维素属于亲水凝胶骨架材料。不溶性骨架材料有乙基纤维素、聚甲基丙烯酸酯、无毒聚氯乙烯、聚乙烯、乙烯—醋酸乙烯共聚物、硅橡胶。亲水性高分子骨架材料有MC、CMC-Na、HPMC、PVP、卡波普、海藻酸盐、脱乙烯壳多糖等。

完形填空

One day, a farmer’s donkey fell into a dry well(井). The poor animal cried for hours before his       finally found him. The farmer tried hard to pull him out from the well but failed. He felt       for the donkey but after carefully thinking about the situation, he       that he would save neither the donkey nor the well. Since the donkey was too       and it was not worth（值得） the trouble of saving. So he invited his neighbors to help him bury(埋葬) the old donkey in the __   so that it would make him end his pain.
     many people coming to help, the old donkey was excited at first. As they began to scoop the dirt into the well with shovels(铲子), he soon       what was happening. He felt upset and cried sadly again. As the farmer and his neighbors continued throwing the dirt on his      , he suddenly had a good idea. Some time later, when the farmer finally looked down into the well, he was surprised at what he saw:     the dirt landed on his back, he would shake it off and take a step up!
Soon, everyone was amazed when the donkey stepped       over the edge of the well and ran away quickly! It seemed that it would       him at first, but it actually helped him later because of the manner in which he faced his adversity(逆境).
That is life! Just like the donkey, life is going to throw dirt on us, all kinds of dirt.     we face our problems in an active way, and refuse to       to any trouble, each dirt is like a stepping stone with which we get out of the deepest wells. This is a key       one of the secrets of life.     stop and never give up. Success is just in its way.

填空题

请从O、N、H、C、He五种元素按要求选择组成相关物质的化学式：

①常温下密度最小的气体______；②能供给人类呼吸的气体______；③最稳定的气体单质______；④有毒性的含碳氧化物______；⑤自然界中硬度最大的物质______；⑥有两种不同原子团的物质______．